1. Field of the Invention
The present invention relates to a disk cartridge for accommodating a disk-shaped information-recording medium such as DVD and MO. In particular, the present invention relates to a disk cartridge which is compact and which makes it easy to insert and remove a disk.
2. Description of the Related Art
As shown in FIG. 7, a disk cartridge 200, which has been hitherto used for the information-recording medium such as DVD, comprises a disk holder 101 for holding a disk 102 and a cartridge case 100 for accommodating the disk holder 101. The cartridge case 100 is a case having a thin thickness with a substantially square surface, and it is principally composed of an upper case and a lower case. Each of the upper case and the lower case is a formed product made of synthetic resin. An internal space is formed by overlapping the upper case and the lower case with each other. An opening 106 is provided on one of side surfaces of the cartridge case 100. The disk holder 101, which holds the disk 102, is inserted in the direction of the arrow AR7 from the opening 106, and thus the disk 102 is accommodated in the disk cartridge 200. An opening 103 is provided on one of the surfaces of the cartridge case 100 (for example, on the upper case). Further, a slidable shutter 104 is provided to cover the opening 103. When the disk cartridge, which accommodates the disk 102, is inserted into an information-recording/reproducing apparatus, a predetermined portion of the information-recording/reproducing apparatus allows the shutter 104 to slide in the direction perpendicular to AR7 to open the opening 103 so that an information-recording/reproducing surface of the disk 102 accommodated in the disk cartridge 200 is exposed. Accordingly, a recording and reproducing head of the information-recording/reproducing apparatus is accessible with respect to the information-recording surface of the disk 102.
However, the disk cartridge having the structure as shown in FIG. 7 has an area which is about 1.6 times the area of the circular plate-shaped disk. The useless space has been consumed in the information-recording/reproducing apparatus in order to accommodate the disk cartridge. The useless space has been one of the factors to obstruct the miniaturization and lower the degree of freedom of the design of the information-recording/reproducing apparatus itself. Further, the conventional disk cartridge has involved such problems that the structure is complicated and the number of parts is increased, because the disk is held by the disk holder. Due to such problems, the production cost of the disk cartridge has been expensive, and it has been inconvenient to accommodate or remove the disk.